#ifndef myalgebra_H_
#define myalgebra_H_
double * minus3(double * a, double * b);
double norm3(double * a);
double * cross3(double * a, double * b);
double pointToLineDistance(double * point,double * pointAonLine, double * pointBonLine);
double pointToPointDistance(double * pointA,double * pointB);
void matmul(double ** A, int rows_a, int cols_a, double ** B, int rows_b, int cols_b, double ** C);
#endif
